Synthesis and Impedance Spectroscope of B-Doped La_9.33+x/3(SiO₄)_6-x(BO₄)_xO₂ Apatite Oxide Ion Conductor

Abstract:

B₂O₃ was doped into the oxide ion conductor La_9.33(SiO₄)₆O₂ according to the formula La_9.33+x/3(SiO₄)_6-x(BO₄)_xO₂ where 0 ≤ x ≤ 2. Samples were prepared by solid state reaction; difficulty was experienced in obtaining fully homogenised products at intermediate x, although they were nominally single-phase by X-ray powder diffraction. A small conductivity enhancement was observed at intermediate B content which further illustrates the important role of La vacancies in optimising the conductivity of La silicates with the apatite structure.

• Periodical: Materials Science Forum (Volume 904)
• Pages: 102-106
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.904.102
• Online since: August 2017
• Authors: Zhao Xiang Huang*, Kan Yu, Jun Liang, Xiao Li Sheng
• Keywords: Apatite, Ceramics, Impedance Spectroscopy, Microstructure, Oxide Ion Conduction

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